Simulation of ball charge and liner wear

Abstract

Ball mills used in the mineral processing industry grind input ore into finer output. However, during this grinding process, ball mill element wear affects grinding performance. In this article, wear models are developed in order to determine how a ball charge size distribution and liner profiles change as a result of wear. Specifically, it was possible to model and then to simulate ball charge and liner wear, two factors that determine ball mill non-stationary behaviour, using results from a ball charge motion model. The ball charge wear model incorporates adhesive and abrasive wear as a function of energy dissipated in crushing, tumbling and grinding zones of the charge motion profile. The liner wear model incorporates abrasive wear with centrifugal and gravitational forces acting on mill liners. Simulation results shows how a ball size distribution evolves in time as well as how two different liner profiles change over time. These results allow for further work in ball mill optimization as a function of this non-stationary mill behaviour.